Generally speaking, the present invention relates a method of open circuiting a variable wire wound resistance element which comprises applying a wire in a number of turns to a length of insulative strip to provide a resistance element; applying an adhesive to a side of the resistance element not to be in contact with an electrical contact so as to bond the wire to said electrically insulative strip at a predetermined location; and severing at least one turn of the turns of wire at the predetermined location to open circuit the resistance element.
This invention pertains to variable wire wound resistors and more particularly to a method of open circuiting such resistors.
Wire wound resistors are used extensively as potentiometers or rheostats to provide a means of varying electrical power in electrical circuits. For the most part the resistors are manufactured by machine wrapping the wire around a strip or electrically insulative base for an extended length. The length of wound wire is then cut into shorter lengths and electrical terminals applied to the shorter lengths. Many times, however, a customer may desire a length that is shorter than that available. In such instances, the supplier must find a way of shortening the effective length of the resistor.
One prior art method of shortening the length was to apply an electrically insulative material, such a suitable plastic, over the length of wire not needed. However, this method has been found to be unacceptable since the plastic would break off leaving exposed wire. It would be far better to provide a more positive means of shortening the effective length of the resistor.